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authorLoic Poulain <loic.poulain@linaro.org>2021-02-09 12:05:55 +0300
committerDavid S. Miller <davem@davemloft.net>2021-02-11 02:11:51 +0300
commitb6ec6b8942700e855aa1a42e04ca9e1f89162de0 (patch)
tree760f84649ac8f0015a694a80ef601af3e66a1ba3 /drivers/net/mhi_net.c
parentddeb9bfa59c711ccbddec1c9fb9ec190caab1a4c (diff)
downloadlinux-b6ec6b8942700e855aa1a42e04ca9e1f89162de0.tar.xz
net: mhi: Add dedicated folder
Create a dedicated mhi directory for mhi-net, mhi-net is going to be split into differente files (for additional protocol support). Signed-off-by: Loic Poulain <loic.poulain@linaro.org> Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'drivers/net/mhi_net.c')
-rw-r--r--drivers/net/mhi_net.c429
1 files changed, 0 insertions, 429 deletions
diff --git a/drivers/net/mhi_net.c b/drivers/net/mhi_net.c
deleted file mode 100644
index b92c2e1f107e..000000000000
--- a/drivers/net/mhi_net.c
+++ /dev/null
@@ -1,429 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0-or-later
-/* MHI Network driver - Network over MHI bus
- *
- * Copyright (C) 2020 Linaro Ltd <loic.poulain@linaro.org>
- */
-
-#include <linux/if_arp.h>
-#include <linux/mhi.h>
-#include <linux/mod_devicetable.h>
-#include <linux/module.h>
-#include <linux/netdevice.h>
-#include <linux/skbuff.h>
-#include <linux/u64_stats_sync.h>
-
-#define MHI_NET_MIN_MTU ETH_MIN_MTU
-#define MHI_NET_MAX_MTU 0xffff
-#define MHI_NET_DEFAULT_MTU 0x4000
-
-struct mhi_net_stats {
- u64_stats_t rx_packets;
- u64_stats_t rx_bytes;
- u64_stats_t rx_errors;
- u64_stats_t rx_dropped;
- u64_stats_t tx_packets;
- u64_stats_t tx_bytes;
- u64_stats_t tx_errors;
- u64_stats_t tx_dropped;
- struct u64_stats_sync tx_syncp;
- struct u64_stats_sync rx_syncp;
-};
-
-struct mhi_net_dev {
- struct mhi_device *mdev;
- struct net_device *ndev;
- struct sk_buff *skbagg_head;
- struct sk_buff *skbagg_tail;
- const struct mhi_net_proto *proto;
- void *proto_data;
- struct delayed_work rx_refill;
- struct mhi_net_stats stats;
- u32 rx_queue_sz;
-};
-
-struct mhi_net_proto {
- int (*init)(struct mhi_net_dev *mhi_netdev);
- struct sk_buff * (*tx_fixup)(struct mhi_net_dev *mhi_netdev, struct sk_buff *skb);
- void (*rx)(struct mhi_net_dev *mhi_netdev, struct sk_buff *skb);
-};
-
-struct mhi_device_info {
- const char *netname;
- const struct mhi_net_proto *proto;
-};
-
-static int mhi_ndo_open(struct net_device *ndev)
-{
- struct mhi_net_dev *mhi_netdev = netdev_priv(ndev);
-
- /* Feed the rx buffer pool */
- schedule_delayed_work(&mhi_netdev->rx_refill, 0);
-
- /* Carrier is established via out-of-band channel (e.g. qmi) */
- netif_carrier_on(ndev);
-
- netif_start_queue(ndev);
-
- return 0;
-}
-
-static int mhi_ndo_stop(struct net_device *ndev)
-{
- struct mhi_net_dev *mhi_netdev = netdev_priv(ndev);
-
- netif_stop_queue(ndev);
- netif_carrier_off(ndev);
- cancel_delayed_work_sync(&mhi_netdev->rx_refill);
-
- return 0;
-}
-
-static int mhi_ndo_xmit(struct sk_buff *skb, struct net_device *ndev)
-{
- struct mhi_net_dev *mhi_netdev = netdev_priv(ndev);
- const struct mhi_net_proto *proto = mhi_netdev->proto;
- struct mhi_device *mdev = mhi_netdev->mdev;
- int err;
-
- if (proto && proto->tx_fixup) {
- skb = proto->tx_fixup(mhi_netdev, skb);
- if (unlikely(!skb))
- goto exit_drop;
- }
-
- err = mhi_queue_skb(mdev, DMA_TO_DEVICE, skb, skb->len, MHI_EOT);
- if (unlikely(err)) {
- net_err_ratelimited("%s: Failed to queue TX buf (%d)\n",
- ndev->name, err);
- dev_kfree_skb_any(skb);
- goto exit_drop;
- }
-
- if (mhi_queue_is_full(mdev, DMA_TO_DEVICE))
- netif_stop_queue(ndev);
-
- return NETDEV_TX_OK;
-
-exit_drop:
- u64_stats_update_begin(&mhi_netdev->stats.tx_syncp);
- u64_stats_inc(&mhi_netdev->stats.tx_dropped);
- u64_stats_update_end(&mhi_netdev->stats.tx_syncp);
-
- return NETDEV_TX_OK;
-}
-
-static void mhi_ndo_get_stats64(struct net_device *ndev,
- struct rtnl_link_stats64 *stats)
-{
- struct mhi_net_dev *mhi_netdev = netdev_priv(ndev);
- unsigned int start;
-
- do {
- start = u64_stats_fetch_begin_irq(&mhi_netdev->stats.rx_syncp);
- stats->rx_packets = u64_stats_read(&mhi_netdev->stats.rx_packets);
- stats->rx_bytes = u64_stats_read(&mhi_netdev->stats.rx_bytes);
- stats->rx_errors = u64_stats_read(&mhi_netdev->stats.rx_errors);
- stats->rx_dropped = u64_stats_read(&mhi_netdev->stats.rx_dropped);
- } while (u64_stats_fetch_retry_irq(&mhi_netdev->stats.rx_syncp, start));
-
- do {
- start = u64_stats_fetch_begin_irq(&mhi_netdev->stats.tx_syncp);
- stats->tx_packets = u64_stats_read(&mhi_netdev->stats.tx_packets);
- stats->tx_bytes = u64_stats_read(&mhi_netdev->stats.tx_bytes);
- stats->tx_errors = u64_stats_read(&mhi_netdev->stats.tx_errors);
- stats->tx_dropped = u64_stats_read(&mhi_netdev->stats.tx_dropped);
- } while (u64_stats_fetch_retry_irq(&mhi_netdev->stats.tx_syncp, start));
-}
-
-static const struct net_device_ops mhi_netdev_ops = {
- .ndo_open = mhi_ndo_open,
- .ndo_stop = mhi_ndo_stop,
- .ndo_start_xmit = mhi_ndo_xmit,
- .ndo_get_stats64 = mhi_ndo_get_stats64,
-};
-
-static void mhi_net_setup(struct net_device *ndev)
-{
- ndev->header_ops = NULL; /* No header */
- ndev->type = ARPHRD_RAWIP;
- ndev->hard_header_len = 0;
- ndev->addr_len = 0;
- ndev->flags = IFF_POINTOPOINT | IFF_NOARP;
- ndev->netdev_ops = &mhi_netdev_ops;
- ndev->mtu = MHI_NET_DEFAULT_MTU;
- ndev->min_mtu = MHI_NET_MIN_MTU;
- ndev->max_mtu = MHI_NET_MAX_MTU;
- ndev->tx_queue_len = 1000;
-}
-
-static struct sk_buff *mhi_net_skb_agg(struct mhi_net_dev *mhi_netdev,
- struct sk_buff *skb)
-{
- struct sk_buff *head = mhi_netdev->skbagg_head;
- struct sk_buff *tail = mhi_netdev->skbagg_tail;
-
- /* This is non-paged skb chaining using frag_list */
- if (!head) {
- mhi_netdev->skbagg_head = skb;
- return skb;
- }
-
- if (!skb_shinfo(head)->frag_list)
- skb_shinfo(head)->frag_list = skb;
- else
- tail->next = skb;
-
- head->len += skb->len;
- head->data_len += skb->len;
- head->truesize += skb->truesize;
-
- mhi_netdev->skbagg_tail = skb;
-
- return mhi_netdev->skbagg_head;
-}
-
-static void mhi_net_dl_callback(struct mhi_device *mhi_dev,
- struct mhi_result *mhi_res)
-{
- struct mhi_net_dev *mhi_netdev = dev_get_drvdata(&mhi_dev->dev);
- const struct mhi_net_proto *proto = mhi_netdev->proto;
- struct sk_buff *skb = mhi_res->buf_addr;
- int free_desc_count;
-
- free_desc_count = mhi_get_free_desc_count(mhi_dev, DMA_FROM_DEVICE);
-
- if (unlikely(mhi_res->transaction_status)) {
- switch (mhi_res->transaction_status) {
- case -EOVERFLOW:
- /* Packet can not fit in one MHI buffer and has been
- * split over multiple MHI transfers, do re-aggregation.
- * That usually means the device side MTU is larger than
- * the host side MTU/MRU. Since this is not optimal,
- * print a warning (once).
- */
- netdev_warn_once(mhi_netdev->ndev,
- "Fragmented packets received, fix MTU?\n");
- skb_put(skb, mhi_res->bytes_xferd);
- mhi_net_skb_agg(mhi_netdev, skb);
- break;
- case -ENOTCONN:
- /* MHI layer stopping/resetting the DL channel */
- dev_kfree_skb_any(skb);
- return;
- default:
- /* Unknown error, simply drop */
- dev_kfree_skb_any(skb);
- u64_stats_update_begin(&mhi_netdev->stats.rx_syncp);
- u64_stats_inc(&mhi_netdev->stats.rx_errors);
- u64_stats_update_end(&mhi_netdev->stats.rx_syncp);
- }
- } else {
- skb_put(skb, mhi_res->bytes_xferd);
-
- if (mhi_netdev->skbagg_head) {
- /* Aggregate the final fragment */
- skb = mhi_net_skb_agg(mhi_netdev, skb);
- mhi_netdev->skbagg_head = NULL;
- }
-
- u64_stats_update_begin(&mhi_netdev->stats.rx_syncp);
- u64_stats_inc(&mhi_netdev->stats.rx_packets);
- u64_stats_add(&mhi_netdev->stats.rx_bytes, skb->len);
- u64_stats_update_end(&mhi_netdev->stats.rx_syncp);
-
- switch (skb->data[0] & 0xf0) {
- case 0x40:
- skb->protocol = htons(ETH_P_IP);
- break;
- case 0x60:
- skb->protocol = htons(ETH_P_IPV6);
- break;
- default:
- skb->protocol = htons(ETH_P_MAP);
- break;
- }
-
- if (proto && proto->rx)
- proto->rx(mhi_netdev, skb);
- else
- netif_rx(skb);
- }
-
- /* Refill if RX buffers queue becomes low */
- if (free_desc_count >= mhi_netdev->rx_queue_sz / 2)
- schedule_delayed_work(&mhi_netdev->rx_refill, 0);
-}
-
-static void mhi_net_ul_callback(struct mhi_device *mhi_dev,
- struct mhi_result *mhi_res)
-{
- struct mhi_net_dev *mhi_netdev = dev_get_drvdata(&mhi_dev->dev);
- struct net_device *ndev = mhi_netdev->ndev;
- struct mhi_device *mdev = mhi_netdev->mdev;
- struct sk_buff *skb = mhi_res->buf_addr;
-
- /* Hardware has consumed the buffer, so free the skb (which is not
- * freed by the MHI stack) and perform accounting.
- */
- dev_consume_skb_any(skb);
-
- u64_stats_update_begin(&mhi_netdev->stats.tx_syncp);
- if (unlikely(mhi_res->transaction_status)) {
-
- /* MHI layer stopping/resetting the UL channel */
- if (mhi_res->transaction_status == -ENOTCONN) {
- u64_stats_update_end(&mhi_netdev->stats.tx_syncp);
- return;
- }
-
- u64_stats_inc(&mhi_netdev->stats.tx_errors);
- } else {
- u64_stats_inc(&mhi_netdev->stats.tx_packets);
- u64_stats_add(&mhi_netdev->stats.tx_bytes, mhi_res->bytes_xferd);
- }
- u64_stats_update_end(&mhi_netdev->stats.tx_syncp);
-
- if (netif_queue_stopped(ndev) && !mhi_queue_is_full(mdev, DMA_TO_DEVICE))
- netif_wake_queue(ndev);
-}
-
-static void mhi_net_rx_refill_work(struct work_struct *work)
-{
- struct mhi_net_dev *mhi_netdev = container_of(work, struct mhi_net_dev,
- rx_refill.work);
- struct net_device *ndev = mhi_netdev->ndev;
- struct mhi_device *mdev = mhi_netdev->mdev;
- int size = READ_ONCE(ndev->mtu);
- struct sk_buff *skb;
- int err;
-
- while (!mhi_queue_is_full(mdev, DMA_FROM_DEVICE)) {
- skb = netdev_alloc_skb(ndev, size);
- if (unlikely(!skb))
- break;
-
- err = mhi_queue_skb(mdev, DMA_FROM_DEVICE, skb, size, MHI_EOT);
- if (unlikely(err)) {
- net_err_ratelimited("%s: Failed to queue RX buf (%d)\n",
- ndev->name, err);
- kfree_skb(skb);
- break;
- }
-
- /* Do not hog the CPU if rx buffers are consumed faster than
- * queued (unlikely).
- */
- cond_resched();
- }
-
- /* If we're still starved of rx buffers, reschedule later */
- if (mhi_get_free_desc_count(mdev, DMA_FROM_DEVICE) == mhi_netdev->rx_queue_sz)
- schedule_delayed_work(&mhi_netdev->rx_refill, HZ / 2);
-}
-
-static struct device_type wwan_type = {
- .name = "wwan",
-};
-
-static int mhi_net_probe(struct mhi_device *mhi_dev,
- const struct mhi_device_id *id)
-{
- const struct mhi_device_info *info = (struct mhi_device_info *)id->driver_data;
- struct device *dev = &mhi_dev->dev;
- struct mhi_net_dev *mhi_netdev;
- struct net_device *ndev;
- int err;
-
- ndev = alloc_netdev(sizeof(*mhi_netdev), info->netname,
- NET_NAME_PREDICTABLE, mhi_net_setup);
- if (!ndev)
- return -ENOMEM;
-
- mhi_netdev = netdev_priv(ndev);
- dev_set_drvdata(dev, mhi_netdev);
- mhi_netdev->ndev = ndev;
- mhi_netdev->mdev = mhi_dev;
- mhi_netdev->skbagg_head = NULL;
- mhi_netdev->proto = info->proto;
- SET_NETDEV_DEV(ndev, &mhi_dev->dev);
- SET_NETDEV_DEVTYPE(ndev, &wwan_type);
-
- INIT_DELAYED_WORK(&mhi_netdev->rx_refill, mhi_net_rx_refill_work);
- u64_stats_init(&mhi_netdev->stats.rx_syncp);
- u64_stats_init(&mhi_netdev->stats.tx_syncp);
-
- /* Start MHI channels */
- err = mhi_prepare_for_transfer(mhi_dev);
- if (err)
- goto out_err;
-
- /* Number of transfer descriptors determines size of the queue */
- mhi_netdev->rx_queue_sz = mhi_get_free_desc_count(mhi_dev, DMA_FROM_DEVICE);
-
- err = register_netdev(ndev);
- if (err)
- goto out_err;
-
- if (mhi_netdev->proto) {
- err = mhi_netdev->proto->init(mhi_netdev);
- if (err)
- goto out_err_proto;
- }
-
- return 0;
-
-out_err_proto:
- unregister_netdev(ndev);
-out_err:
- free_netdev(ndev);
- return err;
-}
-
-static void mhi_net_remove(struct mhi_device *mhi_dev)
-{
- struct mhi_net_dev *mhi_netdev = dev_get_drvdata(&mhi_dev->dev);
-
- unregister_netdev(mhi_netdev->ndev);
-
- mhi_unprepare_from_transfer(mhi_netdev->mdev);
-
- if (mhi_netdev->skbagg_head)
- kfree_skb(mhi_netdev->skbagg_head);
-
- free_netdev(mhi_netdev->ndev);
-}
-
-static const struct mhi_device_info mhi_hwip0 = {
- .netname = "mhi_hwip%d",
-};
-
-static const struct mhi_device_info mhi_swip0 = {
- .netname = "mhi_swip%d",
-};
-
-static const struct mhi_device_id mhi_net_id_table[] = {
- /* Hardware accelerated data PATH (to modem IPA), protocol agnostic */
- { .chan = "IP_HW0", .driver_data = (kernel_ulong_t)&mhi_hwip0 },
- /* Software data PATH (to modem CPU) */
- { .chan = "IP_SW0", .driver_data = (kernel_ulong_t)&mhi_swip0 },
- {}
-};
-MODULE_DEVICE_TABLE(mhi, mhi_net_id_table);
-
-static struct mhi_driver mhi_net_driver = {
- .probe = mhi_net_probe,
- .remove = mhi_net_remove,
- .dl_xfer_cb = mhi_net_dl_callback,
- .ul_xfer_cb = mhi_net_ul_callback,
- .id_table = mhi_net_id_table,
- .driver = {
- .name = "mhi_net",
- .owner = THIS_MODULE,
- },
-};
-
-module_mhi_driver(mhi_net_driver);
-
-MODULE_AUTHOR("Loic Poulain <loic.poulain@linaro.org>");
-MODULE_DESCRIPTION("Network over MHI");
-MODULE_LICENSE("GPL v2");